Rotary well-drilling tool



April 7, 1931.

J. P. DAVIS 1,799,411

ROTARY WELL DRILLING TooL Original Filed May 28, 1928 v/7 L A;

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Patented Apr. 7, 19 31 UNITED STATES JOHN P. DAVIS, or set. LOUIS, MISSOURI, ASSIGNOR TO THE KENNEnYn CORPORAT ON 0]? saw. LOUIS, mssounr, A CORPORATION F DELAWARE,

ROTARY WELL-DRILLING TOOL Application filed May 28, 1923, Serial No. 281,079. Renewed February '21; 1930.

This invention relates more particularly to improvements in rotary well drilling tools, equipped with bit controls in which the drill pipe from the rotary table to the drill bit is divided into two portions, the upper portion delivering rotary power only, while the lower portion transmits not only rotary movement but also pressure against the drill bit Within the limits of the control.

It has been proposed, in the use of conventional' rotary well drilling equipment, to utilize an attachment or device known as a rotary bit control which functions to practically eliminate from the drill pipe all lateral deflection and in addition to permit only a known portion and weight of the drill pipe to rest upon the bit during actual drilling. This rotary bit control in one embodiment comprises a-hollow shaft disposed for independent movement in the casing associated with means carried by the casing for rotating the shaft as a unit with the casing, said hollow shaft being connected with weighted means of known predetermined weight, which weight is interposed between the hollow shaft and the drill bit: 7

The improvement of the present invention more particularly comprises ameans for practically closing off the water forced through the drill pipe by the mud pump 7 at the surface of the ground;

Among the objects of the present invention are to provide a means for practically clos- 'ing off the water forced through the drill pipe by the mud pump; to utilize the downward movement of the rotary bit control in closingoif the water and the upward movement foropening a'valve and furnishing a free passagew'ayfor the water.

In practical'operation it is proposed to overload the pump and cause it to knock or thud, when the rotary bit control reaches its extreme downward position by practically shutting olf the water passing through the drill pipe so thatthe drillers attention will be called to the fact that the rotary bit control hasre'ached its downwardposition and mustbe raised for another drill runbefore the drill bit will continue to cut the forma- V I 17. The end of the pipe :7 may be provided tion.

isinot resting on its valve seat 2.

As a feature, the improvement of the pres- Fig. 2 is a vertical sectlon of the water conent invention is applicable to conventional V trol valve and the rotary well drilling bit control illustrating the assembly ready for operation.

Fig. 3 is a sectional view taken online Of 2. V

' Fig. 4 is a transverse sectional View taken onlinet4ofFig.1. I

Referring more in detail to I the drawings, the water controlvalve of the present invention adapted for use with a rotary well drilling bit control comprises a casting 1 (which of the two may also serve as a couplingfor adjacent sections ofdrill pipe) provided with a conical valve seat 2 and a guide 3 supported' openings 5.

.75 by the ribs r Between the ribs 4; are the In the guide 3 moves thee pipe or valve stem I 7, atthe lower endof Whichis attached a casting 8 provided with openings 9, which casting 8 is adapted to be suitably connected drilling bit control 20.

-with the upper'portion of the rotary well Surrounding the valve ste1n7 and secured in fixed relation movement of the movable conical lift valve 1 11 (as illustrated in Fig. 2) when the latter Surrounding the stem 7 and movable there- .ee V

on isthe washer 12, which functions to e.

tain one end of the compression spring 13 which surrounds pipe 7, theother end of said spring being retained by the jam nut .14. Surrounding the upper end of the pipe7 and Against the bridge'15. is secured the 1' am nut screwed thereon is the centering bridge guide 15- adapted to move withinthe drill pipe l6.

with a cap 18 which in turn may be provided with a small hole 19. V

The assembly of the water control valve and the rotary well drilling bit control is shown in Fig. 2, and its operation is as follows: r

When the tubular control shaft 20 moves downwardly in the drill pipe 16 it carries the pi e 7 and, of course, the valve 11 with it. en shoulder 21 on tubular shaft'20 closely approaches the shoulder 22, the lift valve 11 seats on the valve seat 2, because the distance between the shoulders 21 and 22' is slightly more than the distance from the shoulder 10 on the pipe 7 to the valve seat 2 in the casting 1. As the tubular control shaft 2O continues to move downwardly until shoulder 21 contacts shoulder 22; the spring 13 compresses and holds the valve 11 firmly on its seat 2. When the valve 11 is seated it will be noted that there is no large opening whereby the water may pass through the drill pipe into the tubular control shaft 20. By shutting off the water in this manner, the pump at the surface of the ground which is fcrcing water in the drill pipe 16 will start to pound and the drilling operatorwill he notified that the rotary Well drilling bitcontrol has reached its extreme downward position and must be raised to the position shown in Fi 2 before drilling may proceed.

3 hole 19, as heretofore described, may be provided in the cap .18., if desired, so that a small amount of Water may flow through the drill pipe and out of the drill bit to maintain a circulation of water when the valve 11 is seated or closed. The passage of the small amount of water down the drill pipe and out the drillhole and outside of the drill piperetards the settlement around the drill bit of all cuttings and particles carried by the water. As is wellknown, the

druid pump forces water down the drill pipe during drilling and this water passes through a hole or holes provided in the drill bit and the Water then passes up between the walls of the hole and the outside of the drill pipe and flows Outat the surf-ace of the ground.

"the rings formingshoulders 21 and 22. The

I rotary control shaft 20 is illustrated in two sections. To the lower end of the lower section may be secured common drill pipe (not shown) by a conventional pipe coupling (not shown), and to the endo the common drill pipe may be secured the usual conventional drill bit holder and drill bit (not shown),

the drill pipe below the lower section of the rotary control shaft 20 being Weighted in a suitable manner so as to dispose a known and predetermined weight on the drill bit, the casing 16 above the rotary control shaft 20 being suspended from the rotary table. For general use the most efficient weight on the drill bit has been ascertained to he approximately 10,000 pounds.

In the installation and operation of the rotary Well drilling bit control, the upper end of the pipe 16 is attached by the conventional pipe coupling to the drill pipe leading through the rotary drill table and connected with the control hoist, while the-lower end of the lower section of the rotary control shaft 20 is connected to a drill pipe of the weight desired to rest on the drill bit during 1 actual drilling. V i

With the control hoist, the rotary bit control is lowered into position for drilling and the drill bit is let down until it rests, upon the'formation to be cut and until the drill control shaft 20 is in its'upper position, as illustrated in Fig. 2. The rotary table is then started and as it revolves sowill the drill pipe, control device and the drill bit,

the rotation imparted to the drill pipe by the rotary table in turn being imparted to the hollow shaft 20 through the medium of the ribs 2% and complemental grooves 25. In addition, since the weight of the pipe below the control shaft .20 rests upon the drill bit, the latter will start cutting and proceed downwardly. Through its own weight the control shaft will also move downwardly. When the control shaft 20 has moved downwardly to a point where the shoulder 21 rests upon the shoulder 22, the drill bit will proneed no further and since the bit is not drilling it will spin At this time the valve 11. has

been carried downwardly with the control shaft 20 and, as illustrated in Fig. l, practically shuts off the water being forced through the mud pump. The driller then lowers the drill pipe carried by the rotary table a sulficient distance to again space the shoulders 21 and22 a desired distance apart, after which the drilling may proceed as heretofore described. v

The rotary well drilling bit control is adapted to be placed at any depth below the surface of the ground as a part of the drill pipe transmitting rotary movement and power to drive the drill bit and attached and so arranged in combination With the drill pipe leading to the rotary table at the surface of the ground that the drill pipe carrying within it the rotary well drilling bit control mechanism, and the V drill pipe connected thereto and carrying a drill bit will move upward or downward within the limits of the drill bit control without any upward or" downward movement to the drill pipe leading to the rotary table and attached to th hoist at the surface-of the ground.

I claim as my invention:

1. A rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft slidable in said casing and extending from the lower end thereof, means carried by said casing for rotating said shaft as a unit with the casing, a valve seat carried by the outer casing and a vertically slidable valve movable for a limited distance with said hollow shaft adapted, when the hollow shaft has moved downwardly a predetermined distance, to seat and substantially close OK the supply of water being forced through the hollow shaft.

2. A rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft in said casing, means carried by said casing for rotating said shaft as a unit with the casing, a valve seat carried by the outer casing and a spring tensioned valve cooperatively associated and movable for a limited distance with said hollow shaft adapted, when the hollow shaft has moved downwardly a predetermined distance, to seat and substantially close OK the supply of waterbeing forced through the hollow shaft.

3. A rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft in said casing on the end of which a drill bit is to be carried, means carried by said casing for rotating said shaft as a unit with the casing, a valve stem cooperatively associated and movable with said hollow shaft, a valve loosely mounted on-said valve stem, a valve seat carriedrby the outer casing, and upon which the valve is adapted to operate and a shoulder fixed on said stem adapted to limit the pressure which the valve exerts upon the valve seat.

4. A rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft in said casing, means carried by said casing for rotating said shaft as a unit with the casa valve stem cooperatively associated.

ment of said valve, a valve seat associated with said outer casing, and a tension spring associated with said stem and interposed between the valve and an end of said stem, said spring in expanded position holding said valve against said shoulder and in compressed position holding said valve against said valve seat. d 7

6. A'rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft in said casing, means carried by said casing for rotating said shaft as a unit with the easing, a valve stem cooperatively associated and movable with said hollow shaft, a valve slidably'mounted on said valve stem, a valve seat carried by the said casing, and upon which the valve is adapted to operate, a shoulder fixed on said stem adapted to limit the pressure which the valve exerts upon the valve seat, and means for guiding the movement of said valve stem.

7. A rotary well drilling tool comprising in combination, an outer casing'adapted to be rotatably driven, a movable hollow shaft in said casing on the end of which a drill bit is to be carried, means carried by said casing for rotating said shaft as a unit with the casing, a valve cooperatively associated andmovable for a limited distance with said hollow shaft, a valve seat associated with said outer casing, said valve adapted, when the hollow shaft has moved downwardly a predetermined distance, to. substantially ,close off the supply of water being forced through the hollow shaft.

In testlmony whereof I afiix my signature. JOHN DAVIS.

and movable with said hollow shaft, a valve loosely mounted on said valve stem, a shoulder fixed on said stem adapted to limit the movement of said valve, and a valve seat as sociated with said outer casing.

5. A rotary well drilling tool comprising in combination, an outer casing adapted to be rotatably driven, a movable hollow shaft in said casing, means carried by said casing for rotating said shaft as a unit with the casing, a valve stem cooperatively associated and movable with said hollow shaft, a valve loosely mounted on said valve stem, a shoulder fixed on said stem adapted to limit the move- 

